title: Gold nanoantenna resonance diagnostics via transversal particle plasmon luminescence.
abstract: We perform two-photon excitation confocal experiments on coupled gold nanoantennas and observe time-integrated luminescence spectra that match plasmonic mode emission in the far-field. We show that the transversal particle plasmon mode can be excited, using excitation light that is cross-polarized with respect to the gold luminescence signal and therefore oriented along the long axis of the dipole gold antenna. We provide evidence for losses in polarization information from the excitation channel to the luminescence response due to the nature of the energy and momentum transfer. Finally, we map out the two-photon induced luminescence intensity profile for a fixed excitation wavelength λ and varying antenna arm length L.
authors.affiliation: DFG Heisenberg Group Nanoscale Science, Karlsruhe Institute of Technology, Karlsruhe, Germany.
authors.forename: Matthias D
authors.initials: MD
authors.lastname: Wissert
authors.forename: Carola
authors.initials: C
authors.lastname: Moosmann
authors.forename: Konstantin S
authors.initials: KS
authors.lastname: Ilin
authors.forename: Michael
authors.initials: M
authors.lastname: Siegel
authors.forename: Uli
authors.initials: U
authors.lastname: Lemmer
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Eisler